Mitigating pattern collapse

ABSTRACT

One or more techniques or systems for mitigating pattern collapse are provided herein. For example, a semiconductor structure for mitigating pattern collapse is formed. In some embodiments, the semiconductor structure includes an extreme low-k (ELK) dielectric region associated with a via or a metal line. For example, a first metal line portion and a second metal line portion are associated with a first lateral location and a second lateral location, respectively. In some embodiments, the first portion is formed based on a first stage of patterning and the second portion is formed based on a second stage of patterning. In this manner, pattern collapse associated with the semiconductor structure is mitigated, for example.

RELATED APPLICATION

This application is a divisional of and claims priority to U.S. patentapplication Ser. No. 13/744,485, titled “MITIGATING PATTERN COLLAPSE”and filed on Jan. 18, 2013, which is incorporated herein by reference.

BACKGROUND

Generally, a trench is etched in a region to form a space for a metalline. However, when the trench is deep, complications may occur duringfabrication. For example, one or more trenches often collapse, thusresulting in pattern collapse associated with the region.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the disclosure are understood from the following detaileddescription when read with the accompanying drawings. It will beappreciated that elements, structures, etc. of the drawings are notnecessarily drawn to scale. Accordingly, the dimensions of the same maybe arbitrarily increased or reduced for clarity of discussion, forexample.

FIG. 1 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, according to some embodiments.

FIG. 2 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, according to some embodiments.

FIG. 3 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 4 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 5 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 6 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 7 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 8 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 9 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 10 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 11 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 12 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 13 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 14 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 15 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 16 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 17 is a cross-sectional view of an example semiconductor structurefor mitigating pattern collapse, during formation, according to someembodiments.

FIG. 18 is a flow diagram of an example method for forming asemiconductor structure associated with mitigating pattern collapse,according to some embodiments.

DETAILED DESCRIPTION

Embodiments or examples, illustrated in the drawings are disclosed belowusing specific language. It will nevertheless be understood that theembodiments or examples are not intended to be limiting. Any alterationsand modifications in the disclosed embodiments, and any furtherapplications of the principles disclosed in this document arecontemplated as would normally occur to one of ordinary skill in thepertinent art.

It will be appreciated that ‘layer’, as used herein, contemplates aregion, and does not necessarily comprise a uniform thickness. Forexample, a layer is a region, such as an area comprising arbitraryboundaries. For another example, a layer is a region comprising at leastsome variation in thickness.

It will be appreciated that for at least some of the figures herein, oneor more boundaries, such as boundary 104 of FIG. 1, for example, aredrawn with different heights, widths, perimeters, aspect ratios, etc.relative to one another merely for illustrative purposes, and are notnecessarily drawn to scale. For example, because dashed or dotted linesare used to represent different boundaries, if the dashed and dottedlines were drawn on top of one another they would not be distinguishablein the figures, and thus are drawn slightly apart from one another, inat least some of the figures, so that they are distinguishable from oneanother, for example. As another example, because a region is associatedwith an irregular shape, a box drawn with a dashed line, dotted lined,etc. does not necessarily encompass an entire region. Similarly, a drawnbox does not necessarily encompass merely the associated region, butencompasses at least some of one or more other region as well, in someembodiments. Accordingly, dimensions of some of these boundaries aredrawn taller, shorter, wider, narrower, etc. than needed in someembodiments so that the different boundaries are visible in the figures,for example.

The following figures illustrate formation of an example semiconductorstructure during semiconductor fabrication, according to someembodiments. It will be appreciated that at least some of the respectivefigures are described with reference to one another, such as withreference to a previous figure, for example. However, at least some ofthe respective figures are not described with reference to the previousfigure. For example, according to some embodiments, FIG. 15 is notdescribed with reference to FIG. 14.

FIG. 1 is a cross-sectional view 100 of an example semiconductorstructure for mitigating pattern collapse, according to someembodiments. In some embodiments, the semiconductor structure of FIG. 1comprises a first etch stop layer (ESL) 102. Additionally, thesemiconductor structure comprises an extreme low-k (ELK) dielectricregion 104. In some embodiments, the ELK dielectric region 104 comprisesa first ELK dielectric region 104A and a second ELK dielectric region104B. In some embodiments, the first ELK dielectric region 104A is aboveat least some of the first ESL 102. In some embodiments, the second ELKdielectric region 104B is above at least some of the first ELKdielectric region 104A. For example, the second ELK dielectric region104B is above boundary 190. In some embodiments, at least some of atleast one of the ELK dielectric region 104, the first ELK dielectricregion 104A, or the second ELK dielectric region 104B comprises at leastone of a metal line, or an additional metal line associated with a via.

For example, the metal line comprises a first metal line portion 110 anda second metal line portion 120. In some embodiments, the first metalline portion 110 is associated with a first lateral metal line locationand the second metal line portion 120 is associated with a secondlateral metal line location. Additionally, an additional metal linecomprises a first metal line portion 130 and a second metal line portion140. In some embodiments, the additional metal line is associated with avia portion 1930. In some embodiments, the first metal line portion 130is associated with a first lateral location and the second metal lineportion 140 is associated with a second lateral location. In someembodiments, the via portion 1930 is associated with the first laterallocation. In some embodiments, the second lateral metal line location isdifferent from the first lateral metal line location. In someembodiments, the second lateral location is different from the firstlateral location. In some embodiments, at least one of the first metalline portion 130, the first metal line portion 110, or the via portion1930 is formed based on a first stage of patterning. In someembodiments, at least one of the second metal line portion 140 or thesecond metal line portion 120 are formed based on a second stage ofpatterning. In some embodiments, the second metal line portion 140 isabove at least some of the first metal line portion 130. In someembodiments, at least some of the first metal line portion 130 is aboveat least some of the via portion 1930. In some embodiments, the secondmetal line portion 120 is above at least some of the first metal lineportion 110.

In some embodiments, the additional metal line comprises a first barrierportion 132 associated with a first lateral barrier location. In someembodiments, the additional metal line is associated with a via barrierportion 1932 associated with the first lateral barrier location. In someembodiments, the additional metal line comprises a second barrierportion 142 associated with a second lateral barrier location. Forexample, the second lateral barrier location is different from the firstlateral barrier location, at least because the first barrier portion 132is formed based on a first stage of patterning and the second barrierportion 142 is formed based on a second stage of patterning. In someembodiments, the second barrier portion 142 is above at least some ofthe first barrier portion 132. In some embodiments, the first barrierportion 132 is above at least some of the via barrier portion 1932. Insome embodiments, a difference between the second lateral barrierlocation and the first lateral barrier location is less than tennanometers. In other words, an offset associated with the respectivebarrier portions 142 and 132 is about ten nanometers.

In some embodiments, the metal line comprises a first metal line barrierportion 112 associated with a first lateral metal line barrier location.In some embodiments, the metal line comprises a second metal linebarrier portion 122 associated with a second lateral metal linelocation. For example, the second lateral metal line barrier location isdifferent from the first lateral metal line barrier location, at leastbecause the first metal line barrier portion 112 is formed based on afirst stage of patterning and the second metal line barrier portion 122is formed based on a second stage of patterning. In some embodiments,the second metal line barrier portion 122 is above at least some of thefirst metal line barrier portion 112. In some embodiments, a differencebetween the second lateral metal line barrier location and the firstlateral metal line barrier location is less than ten nanometers. Inother words, an offset associated with the respective metal line barrierportions 122 and 112 is about ten nanometers.

In some embodiments, a barrier layer 192 is formed between at least someof at least one of the second barrier portion 142 and the second ELKdielectric region 104B, the second barrier portion 142 and the first ELKdielectric region 104A, the second barrier portion 142 and the firstmetal line portion 130, the first metal line portion 130 and the secondmetal line portion 140, the second barrier portion 142 and the firstbarrier portion 132, or the first barrier portion 132 and the secondmetal line portion 140. In some embodiments, the barrier layer 192 isformed along a space etched for the additional metal line, for example.In some embodiments, the barrier layer 192 is formed by atomic layerdeposition (ALD).

In some embodiments, a barrier layer 194 is formed between at least someof at least one of the second metal line barrier portion 122 and thesecond ELK dielectric region 104B, second metal line barrier portion 122and the first ELK dielectric region 104A, second metal line barrierportion 122 and the first metal line portion 110, the first metal lineportion 110 and the second metal line portion 120, the second metal linebarrier portion 122 and the first metal line barrier portion 112, or thefirst metal line barrier portion 112 and the second metal line portion120. In some embodiments, the barrier layer 194 is formed along a trenchetched for the metal line, for example. In some embodiments, the barrierlayer 194 is formed by atomic layer deposition (ALD).

In some embodiments, the first barrier portion 132 is associated with afirst barrier composition and a first barrier thickness. In someembodiments, the via barrier portion 1932 is associated with the firstbarrier composition and the first barrier thickness. In someembodiments, the first metal line barrier portion 112 is associated witha first barrier composition and a first barrier thickness 186. Forexample, the first barrier portion 132 and the first metal line barrierportion 112 are associated with the same barrier composition and barrierthickness. In some embodiments, the second barrier portion 142 isassociated with a second barrier composition and a second barrierthickness. In some embodiments, the second metal line barrier portion122 is associated with a second barrier composition and a second barrierthickness 188. For example, the second barrier portion 142 and thesecond metal line barrier portion 122 are associated with the samebarrier composition and barrier thickness. In some embodiments, thesecond barrier composition is different from the first barriercomposition. Similarly, in some embodiments, the second barrierthickness 188 is different from the first barrier thickness 186. In someembodiments, the second barrier composition is the same as the firstbarrier composition. In some embodiments, the second barrier thickness188 is the same as the first barrier thickness 186.

In some embodiments, the first ELK dielectric region 104A comprises thefirst metal line portion 130, the via portion 1930, and the first metalline portion 110. Additionally, in some embodiments, the first ELKdielectric region 104A comprises the first barrier portion 132, the viabarrier portion 1932, and the first metal line barrier portion 112. Itwill be appreciated that at least some of the via portion 1930 or thebarrier runs through the first ESL, according to some embodiments.

In some embodiments, the second ELK dielectric region 104B comprises thesecond metal line portion 140 and the second metal line portion 120.Additionally, in some embodiments, the second ELK dielectric region 104Bcomprises the second barrier portion 142 and the second metal linebarrier portion 122. In some embodiments, the second ELK dielectricregion 104B comprises one or more barrier regions, such as 192 and 194.

FIG. 2 is a cross-sectional view 200 of an example semiconductorstructure for mitigating pattern collapse, according to someembodiments. In some embodiments, the semiconductor structure of FIG. 2comprises a first etch stop layer (ESL) 102. Additionally, thesemiconductor structure comprises an extreme low-k (ELK) dielectricregion 104. In some embodiments, the ELK dielectric region 104 comprisesone or more ELK dielectric regions. For example, the ELK dielectricregion 104 comprises a first ELK dielectric region 104A, a second ELKdielectric region 104B, and a third ELK dielectric region 104C. In someembodiments, the first ELK dielectric region 104A is above at least someof the first ESL 102. In some embodiments, a second ESL 202 is above atleast some of the first ELK dielectric region 104A. In some embodiments,the second ELK dielectric region 104B is above at least some of thesecond ESL 202. In some embodiments, a third ESL 204 is above at leastsome of the second ELK dielectric region 104B. In some embodiments, thethird ELK dielectric region 104C is above at least some of the third ESL204. In some embodiments, at least some of at least one of the ELKdielectric region 104, the first ELK dielectric region 104A, the secondELK dielectric region 104B, or the third ELK dielectric region 104Ccomprises at least one of a metal line or an additional metal lineassociated with a via.

In some embodiments, the metal line comprises one or more metal lineportions. For example, the metal line comprises a first metal lineportion 110, a second metal line portion 120, and a third metal lineportion 230. In some embodiments, the first metal line portion 110 isassociated with a first lateral metal line location, the second metalline portion 120 is associated with a second lateral metal linelocation, and the third metal line portion 230 is associated with athird lateral metal line location. In some embodiments, an additionalmetal line comprises one or more metal line portions. In someembodiments, the additional metal line is associated with a via portion1930. For example, the additional metal line comprises a first metalline portion 130, a second metal line portion 140, and a third metalline portion 250. In some embodiments, the first metal line portion 130is associated with a first lateral location, the second metal lineportion 140 is associated with a second lateral location, and the thirdmetal line portion 250 is associated with a third lateral location. Insome embodiments, the via portion 1930 is associated with the firstlateral location. In some embodiments, at least one of the lateral metalline locations is different from at least one of the other lateral metalline locations. For example, the second lateral metal line location isdifferent from the first lateral metal line location, the second lateralmetal line location is different from the third lateral metal linelocation, or the third lateral metal line location is different from thefirst lateral metal line location. Similarly, at least one of thelateral locations is different from at least one of the other laterallocations. For example, the second lateral location is different fromthe first lateral location, the second lateral location is differentfrom the third lateral location, or the third lateral location isdifferent from the first lateral location.

In some embodiments, at least one of the first metal line portion 130,the via portion 1930, or the first metal line portion 110 is formedbased on a first stage of patterning. In some embodiments, at least oneof the second metal line portion 140 or the second metal line portion120 are formed based on a second stage of patterning. In someembodiments, at least one of the third metal line portion 250 or thethird metal line portion 230 is formed based on a third stage ofpatterning. It will be appreciated, however, that any number of stagesof patterning is used to achieve at least one of via formation or metalline formation associated with the semiconductor structure of FIG. 2,for example. In some embodiments, the second metal line portion 140 isabove at least some of the first metal line portion 130. In someembodiments, the first metal line portion is above at least some of thevia portion 1930. In some embodiments, the second metal line portion 120is above at least some of the first metal line portion 110. In someembodiments, the third metal line portion 250 is above at least some ofthe second metal line portion 140. In some embodiments, the third metalline portion 230 is above at least some of the second metal line portion120.

In some embodiments, the additional metal line comprises one or morebarrier portions associated with one or more corresponding lateralbarrier locations. In some embodiments, the additional metal line isassociated with a via barrier portion 1932. For example, the additionalmetal line comprises a first barrier portion 132 associated with a firstlateral barrier location, a second barrier portion 142 associated with asecond lateral barrier location, and a third barrier portion 252associated with a third lateral barrier location. In some embodiments,the via barrier portion 1932 is associated with the first lateralbarrier location. In some embodiments, at least one of the lateralbarrier locations is different from at least one of the other lateralbarrier locations. For example, the second lateral barrier location isdifferent from the first lateral barrier location, the second lateralbarrier location is different from the third lateral barrier location,or the third lateral barrier location is different from the firstlateral barrier location. In some embodiments, at least one of the firstbarrier portion 132 or the via barrier portion 1932 is formed based on afirst stage of patterning, the second barrier portion 142 is formedbased on a second stage of patterning, and the third barrier portion 252is formed based on a third stage of patterning. In some embodiments, thesecond barrier portion 142 is above at least some of the first barrierportion 132. In some embodiments, the third barrier portion 252 is aboveat least some of the second barrier portion 142.

In some embodiments, the metal line comprises one or more metal linebarrier portions associated with one or more corresponding lateral metalline barrier locations. For example, the metal line comprises a firstmetal line barrier portion 112 associated with a first lateral metalline barrier location, a second metal line barrier portion 122associated with a second lateral metal line barrier location, and athird metal line barrier portion 232 associated with a third lateralmetal line barrier location. In some embodiments, at least one of thelateral metal line barrier locations is different from at least one ofthe other lateral metal line barrier locations. For example, the secondlateral metal line barrier location is different from the first lateralmetal line barrier location, the second lateral metal line barrierlocation is different from the third lateral metal line barrierlocation, or the third lateral metal line barrier location is differentfrom the first lateral metal line barrier location. In some embodiments,the first metal line barrier portion 112 is formed based on a firststage of patterning, the second metal line barrier portion 122 is formedbased on a second stage of patterning, and the third metal line barrierportion 232 is formed based on a third stage of patterning. In someembodiments, the second metal line barrier portion 122 is above at leastsome of the first metal line barrier portion 112. In some embodiments,the third metal line barrier portion 232 is above at least some of thesecond metal line barrier portion 122.

In some embodiments, the metal line is associated with an aspect ratio.For example, the aspect ratio of the metal line is determined based on adepth of a metal line 296 and a spacing distance 298. In someembodiments, the spacing distance 298 is a distance between one or moremetal lines (not shown). In some embodiments, an interface barrier 292is formed between at least some of the first metal line portion 110 andthe second metal line portion 120. In some embodiments, an interfacebarrier 282 is formed between at least some of the second metal lineportion 120 and the third metal line portion 230. Similarly, aninterface barrier 294 is formed between at least some of the first metalline portion 130 and the second metal line portion 140 in someembodiments. Additionally, an interface barrier 284 is formed between atleast some of the second metal line portion 140 and the third metal lineportion 250 in some embodiments. In some embodiments, a barrier layer(not shown) is formed between one or more respective regions.

In some embodiments, the first barrier portion 132 is associated with afirst barrier composition and a first barrier thickness. In someembodiments, the via barrier portion 1932 is associated with the firstbarrier composition and the first barrier thickness. In someembodiments, the first metal line barrier portion 112 is associated witha first barrier composition and a first barrier thickness 186. Forexample, the first barrier portion 132, the via barrier portion 1932,and the first metal line barrier portion 112 are associated with thesame barrier composition and barrier thickness. In some embodiments, thesecond barrier portion 142 is associated with a second barriercomposition and a second barrier thickness. In some embodiments, thesecond metal line barrier portion 122 is associated with a secondbarrier composition and a second barrier thickness 188. For example, thesecond barrier portion 142 and the second metal line barrier portion 122are associated with the same barrier composition and barrier thickness.In some embodiments, the third barrier portion 252 is associated with athird barrier composition and a third barrier thickness. In someembodiments, the third metal line barrier portion 232 is associated witha third barrier composition and a third barrier thickness 288. Forexample, the third barrier portion 252 and the third metal line barrierportion 232 are associated with the same barrier composition and barrierthickness. In some embodiments, at least one of the barrier compositionsis different from at least one of the other barrier compositions. Forexample, the second barrier composition is different from the firstbarrier composition, the second barrier composition is different fromthe third barrier composition, or the third barrier composition isdifferent from the first barrier composition. In other embodiments, thebarrier compositions are the same. In other words, the first barriercomposition is the same as the second barrier composition and the thirdbarrier composition. In some embodiments, at least one of the barrierthicknesses is different from at least one of the other barrierthicknesses. For example, the second barrier thickness 188 is differentfrom the first barrier thickness 186, the second barrier thickness 188is different from the third barrier thickness 288, or the third barrierthickness 288 is different from the first barrier thickness 186. Inother embodiments, the first barrier thickness 186 is the same as thesecond barrier thickness 188 and the third barrier thickness 288.

FIG. 3 is a cross-sectional view 300 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a first etch stop layer (ESL)is formed 102. In some embodiments, a first extreme low-k (ELK)dielectric region 104A is formed above at least some of the first ESL102. In some embodiments, a first cap region 304 is formed above atleast some of the first ELK dielectric region 104A. In some embodiments,a first hard mask (HM) region 306 is formed above at least some of thefirst cap region 304. It will be appreciated that boundary 190 indicatesa boundary associated with the semiconductor structure after a firststage of patterning. In some embodiments, 310 is associated with a firstlateral metal line location of a first metal line portion, such as thefirst metal line portion 110 of FIG. 1, for example. In someembodiments, 312 is associated with a first lateral metal line barrierlocation of a first metal line barrier portion, such as the first metalline barrier portion 112 of FIG. 1, for example.

FIG. 4 is a cross-sectional view 400 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In FIG. 4, a first trench portion 410 of a trench(not entirely shown) is etched within at least a portion of the firstELK dielectric region 104A. For example, the trench is not entirelyillustrated by FIG. 4, at least because two or more stage patterning isused to form trench portions and metal line portions such that thetrench of the semiconductor structure is not completely etched based ona single stage, for example. It will be appreciated that the firsttrench portion 410 is associated with a first trench portion aspectratio determined based on a first trench depth 402 and a trench totrench spacing 404. In some embodiments, the first trench portion aspectratio is the first trench depth 402 divided by the trench to trenchspacing 404. In some embodiments, etching associated with one or moreELK dielectric regions is controlled such that a corresponding aspectratio is less than four. In some embodiments, a trench is etched in anELK dielectric region such that the trench is associated with an aspectratio from at least about 2.5 to at least about 3.5. Accordingly, insome embodiments, the first trench portion 410 of the trench is etchedwithin at least a portion of the first ELK dielectric region 104A basedon a first aspect ratio. For example, the first aspect ratio is lessthan four. For another example, the first aspect ratio is from at leastabout 2.5 to at least about 3.5. In this way, pattern collapseassociated with the first trench portion 410 of the trench of thesemiconductor structure is mitigated, at least because an aspect ratioassociated with the first trench portion 410 is controlled such that thefirst trench portion 410 is not etched in a marginally stable manner,for example. In other words, the first trench portion 410 is not etcheddeep enough for an increased risk of collapse. In some embodiments, afirst wet clean is performed after etching the first trench portion 410of the trench. In some embodiments, the etching of the first ELKdielectric region 104A is based on patterning the first HM region 306.

FIG. 5 is a cross-sectional view 500 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a first metal line barrierportion 112 of a metal line barrier is formed within the first trenchportion 410 of the trench of FIG. 4, for example. In some embodiments,the first metal line barrier portion 112 is formed at least one of alonga floor of the first ELK dielectric region 104A, along a wall of thefirst ELK dielectric region 104A, along a wall of the first cap region304, along a wall of the first HM region 306, or above at least some ofthe first HM region 306 (not shown). In some embodiments, the firstmetal line barrier portion 112 is formed at a first lateral metal linebarrier location, such as 312 of FIG. 3, for example. Accordingly, thefirst metal line barrier portion 112 is formed at a first lateral metalline barrier location within the first ELK dielectric region 104A. Insome embodiments, the first metal line barrier portion 112 is associatedwith at least one of a first barrier composition or a first barrierthickness. In some embodiments, a first metal line portion 110 is formedwithin the first trench portion 410 of the trench of FIG. 4, forexample. In some embodiments, the first metal line portion 110 is formedabove at least some of the first metal line barrier portion 112. In someembodiments, the first metal line portion 110 is formed at a firstlateral metal line location, such as 310 of FIG. 3, for example.Accordingly, the first metal line portion 110 of a metal line is formedat a first lateral metal line location within the first ELK dielectricregion 104A.

FIG. 6 is a cross-sectional view 600 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, at least some of at least oneof the first metal line barrier portion 112 above the first HM region306 or the first metal line portion 110 above the first HM region 306 isremoved. In some embodiments, at least some of the first HM region 306is removed. In some embodiments, at least some of the first cap region304 is removed. In some embodiments, at least some of at least one ofthe first ELK dielectric region 104A above boundary 190, the first metalline portion 110 above boundary 190, or the first metal line barrierportion 112 above boundary 190 is removed. For example, at least some ofthe respective regions are removed by performing a first chemicalmechanical planarization (CMP). In some embodiments, the first CMP isperformed on at least some of at least one of the first ELK dielectricregion 104A, the first metal line portion 110 of the metal line, or thefirst metal line barrier portion 112 of the metal line barrier. In thisway, the semiconductor structure of FIG. 6 is associated with a surfacethat is substantially flush with boundary 190, for example. It will beappreciated that in some embodiments, techniques disclosed, such astechniques associated with FIG. 3-FIG. 6 are implemented to facilitateformation of a semiconductor structure, such as the semiconductorstructure of FIG. 1 or FIG. 2, for example.

Accordingly, FIG. 7 is a cross-sectional view 700 of an examplesemiconductor structure for mitigating pattern collapse, duringformation, according to some embodiments. For example, a second ELKdielectric region 104B is formed above at least some of at least one ofthe first metal line portion 110 of the metal line, the first ELKdielectric region 104A, or the first metal line barrier portion 112. Insome embodiments, the second ELK dielectric region is generally formedabove boundary 190. In some embodiments, a second cap 804 is formedabove at least some of the second ELK dielectric region 104B. In someembodiments, a second HM region 806 is formed above at least some of thesecond cap region 804. It will be appreciated that boundary 890indicates a boundary associated with the semiconductor structure after asecond stage of patterning. In some embodiments, 810 is associated witha second lateral metal line location of a second metal line portion. Insome embodiments, 812 is associated with a second lateral metal linebarrier location of a second metal line barrier portion. It will beappreciated that in some embodiments, the second lateral metal linebarrier location is different from the first lateral metal line barrierlocation. Similarly, the second lateral metal line location is differentfrom the first lateral metal line location, in some embodiments.

FIG. 8 is a cross-sectional view 800 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. FIG. 8 is similar to FIG. 7, except that a secondESL region 202 is formed above boundary 190. In some embodiments, thesecond ESL region 202 is formed above at least some of at least one ofthe first metal line portion 110 of the metal line, the first ELKdielectric region 104A, or the first metal line barrier portion 112. Insome embodiments, the second ELK dielectric region 104B is formed aboveat least some of the second ESL region 202. In this way, one or moreadditional regions are formed between the first ELK dielectric region104A and the second ELK dielectric region 104B. It will be appreciated,however, that any number of regions are formed between or within any ofthe respective regions according to some embodiments. For example, insome embodiments, one or more additional regions are formed within thefirst ELK dielectric region 104A. In some embodiments, at least one ofthe additional regions is an ESL region. In some embodiments, at leastone of the additional regions is an oxide region.

FIG. 9 is a cross-sectional view 900 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a second trench portion 910 ofthe trench is etched within at least a portion of the second ELKdielectric region 104B based on a second aspect ratio. In FIG. 9, asecond trench portion 910 of a trench is etched within at least aportion of the second ELK dielectric region 104B. It will be appreciatedthat according to some embodiments, FIG. 9 is associated with a secondstage of patterning for trench formation. In some embodiments, thesecond trench portion 910 is associated with a second trench portionaspect ratio. For example, the second trench portion aspect ratio isdetermined based on a second trench depth 902 and a second trench totrench spacing 904. In some embodiments, second trench portion aspectratio is the second trench depth 902 divided by the second trench totrench spacing 904. In some embodiments, the second trench portion 910is etched such that an associated second trench portion aspect ratio isless than four. For example, the second trench portion aspect ratio isfrom at least about 2.5 to at least about 3.5. In this way, patterncollapse associated with the second trench portion 910 of the trench ofthe semiconductor structure is mitigated, at least because an aspectratio associated with the second trench portion 910 is controlled suchthat the second trench portion 910 is not etched in an unstable manner,for example. In some embodiments, a second wet clean is performed afteretching the second trench portion 910 of the trench. In someembodiments, the etching of the second ELK dielectric region 104A isbased on patterning the second HM region 806.

FIG. 10 is a cross-sectional view 1000 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a barrier layer 1102 isdeposited. For example, the barrier layer 1102 is formed based on atomiclayer deposition (ALD). In some embodiments, the barrier layer 1102 isformed at least one of above a floor of the second trench portion 910,along a wall of the second trench portion 910, above at least some ofthe second HM region 806, along a wall of the second HM region 806,along a wall of the second cap region 804, along a wall of the secondELK dielectric region 104B, or above border 190, for example.

FIG. 11 is a cross-sectional view 1100 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a second metal line barrierportion 122 is formed. In some embodiments, the second metal linebarrier portion 122 is formed at least one of above a floor of thesecond trench portion 910, along a wall of the second trench portion910, above at least some of the second HM region 806, along a wall ofthe second HM region 806, along a wall of the second cap region 804,along a wall of the second ELK dielectric region 104B, or above border190, for example. In some embodiments, a second metal line barrierportion 122 of a metal line barrier is formed within the second trenchportion 910 of the trench of FIG. 9, for example. In some embodiments,the second metal line barrier portion 122 is formed at a second lateralmetal line barrier location, such as at 812 of FIG. 8, for example.Accordingly, the second metal line barrier portion 122 is formed at asecond lateral metal line barrier location within the second ELKdielectric region 104B. In some embodiments, the second metal linebarrier portion 122 is associated with at least one of a second barriercomposition or a second barrier thickness. It will be appreciated thatin some embodiments, the second barrier thickness is different from thefirst barrier thickness of the first metal line barrier portion 112.Similarly, in some embodiments, the second barrier composition isdifferent from the first barrier composition of the first metal linebarrier portion 112.

FIG. 12 is a cross-sectional view 1200 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, a second metal line portion120 is formed. In some embodiments, the second metal line portion 120 isformed above at least some of the second metal line barrier portion 122.In some embodiments, the second metal line portion 120 is formed aboveat least some of the second HM region 806. In some embodiments, thesecond metal line portion 120 is formed within the second trench portion910 of the trench of FIG. 9, for example. In some embodiments, thesecond metal line portion 120 is formed at a second lateral metal linelocation, such as 810 of FIG. 8, for example. Accordingly, the secondmetal line portion 120 of a metal line is formed at a second lateralmetal line location within the second ELK dielectric region 104B.

FIG. 13 is a cross-sectional view 1300 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, the second metal line barrierportion 122 is annealed. In some embodiments, the semiconductorstructure of FIG. 13 is annealed. In this way, portions of the secondmetal line barrier portion 122 between the first metal line portion 110and the second metal line portion 120 diffuse to come in contact withthe second ELK dielectric region 104B. In some embodiments, theannealing results in a top barrier layer 1422. In some embodiments,annealing the second metal line barrier portion 122 mitigates aninterface barrier between the first metal line portion 110 and thesecond metal line portion 120, such as interface barrier 292 of FIG. 2,for example. In this way, a self-formed barrier 1322 is formed. In someembodiments, a composition associated with the second metal line barrierportion 122 changes based on oxidation, for example.

FIG. 14 is a cross-sectional view 1400 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, at least some of the topbarrier layer 1422 is removed. In some embodiments, at least some of thesecond metal line portion 120 above the second HM region 806 is removed.In some embodiments, at least some of the self-formed barrier 1322 abovethe second HM region 806 is removed. Additionally, at least some of atleast one of the second HM region 806 or the second cap region 804 isremoved. In some embodiments, at least some of at least one of theself-formed barrier 1322 above boundary 890, the second metal lineportion 120 above boundary 890, or the second ELK dielectric region 104Babove boundary 890 is removed. For example, a second CMP is performed onat least some of at least one of the second ELK region 104B, the secondmetal line portion 120, the second metal line barrier portion 122, orthe self-formed barrier 1322. In this way, the semiconductor structureof FIG. 14 is associated with a surface that is substantially flush withboundary 890, for example.

FIG. 15 is a cross-sectional view 1500 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. According to some aspects, FIG. 15 is describedwith respect to FIG. 11, for example. In some embodiments, at least someof the second metal line barrier portion 122 of FIG. 11 is re-sputtered.For example, at least a portion of the second metal line barrier portion122 associated with a floor of the second trench portion 910 of FIG. 9is removed. In some embodiments, a bottom portion 1502 of the secondmetal line barrier portion 122 is removed based on re-sputtering.

FIG. 16 is a cross-sectional view 1600 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, the second metal line portion120 is formed at least some of at least one of above boundary 190, abovethe first metal line portion 110, or above the first metal line barrierportion 112. In some embodiments, the second metal line portion 120 isformed above at least some of the second HM region 806. In someembodiments, the second metal line portion 120 is formed within thesecond trench portion 910 of the trench of FIG. 9, for example. In someembodiments, the second metal line portion 120 is formed at a secondlateral metal line location, such as 810 of FIG. 8, for example.Accordingly, the second metal line portion 120 of a metal line is formedat a second lateral metal line location within the second ELK dielectricregion 104B.

FIG. 17 is a cross-sectional view 1700 of an example semiconductorstructure for mitigating pattern collapse, during formation, accordingto some embodiments. In some embodiments, at least some of the secondmetal line portion 120 above the second HM region 806 is removed. Insome embodiments, at least some of the second metal line barrier portion122 above the second HM region 806 is removed. Additionally, at leastsome of at least one of the second HM region 806 or the second capregion 804 is removed. In some embodiments, at least some of at leastone of the second metal line barrier portion 122 above boundary 890, thesecond metal line portion 120 above boundary 890, or the second ELKdielectric region 104B above boundary 890 is removed. For example, asecond CMP is performed on at least some of at least one of the secondELK region 104B, the second metal line portion 120, or the second metalline barrier portion 122. In this way, the semiconductor structure ofFIG. 16 is associated with a surface that is substantially flush withboundary 890, for example.

FIG. 18 is a flow diagram of an example method 1800 for forming asemiconductor structure associated with mitigating pattern collapse,according to some embodiments. At 1802, the method comprises etching afirst trench portion within a first ELK dielectric region. At 1804, themethod comprises forming a first metal line portion. At 1806, the methodcomprises forming a second ELK dielectric region. At 1808, the methodcomprises etching a second trench portion. At 1810, the method comprisesforming a second metal line portion. It will be appreciated that anynumber of metal line portions is formed in this manner. For example, insome embodiments, the method comprises forming a third ELK dielectricregion above at least some of at least one of the second ELK dielectricregion or the second metal line portion of the metal line. In someembodiments, the method comprises forming a third cap region above atleast some of the third ELK dielectric region. In some embodiments, themethod comprises forming a third hard mask (HM) region above at leastsome of the third cap region. In some embodiments, the method comprisesetching a third trench portion of the trench within at least a portionof the third ELK dielectric region based on a third aspect ratio. Insome embodiments, the method comprises forming a third metal lineportion of the metal line within the third trench portion of the trenchand performing a third chemical mechanical planarization (CMP) on atleast some of at least one of the third ELK dielectric region or thethird metal line portion of the metal line.

One or more techniques or systems for mitigating pattern collapse areprovided herein. Generally, one or more trenches are etched within aregion, and one or more corresponding metal lines are formed within therespective trenches. In some embodiments, respective metal lines or viasare formed based on two or more stage patterning. In this way, patterncollapse associated with respective trenches within the region ismitigated. For example, a semiconductor structure comprises an extremelow-k (ELK) dielectric region. In some embodiments, the ELK dielectricregion comprises at least one of a metal line or an additional metalline associated with a via. In some embodiments, a metal line comprisesone or more metal line portions. For example, the metal line comprises afirst metal line portion associated with a first lateral location and asecond metal line portion associated with a second lateral location. Insome embodiments, the second lateral location is different from thefirst lateral location. For example, the metal line comprises a firstmetal line portion associated with a first lateral metal line locationand a second metal line portion associated with a second lateral metalline location. In some embodiments, the second lateral metal linelocation is different from the first lateral metal line location.

In some embodiments, a first metal line portion is formed based on afirst stage of patterning and a second metal line portion is formedbased on a second stage of patterning. In other words, the first metalline portion is not necessarily lined up with the second metal lineportion, at least because a mask alignment associated with the firststage of patterning is not exactly the same as a mask alignmentassociated with the second stage of patterning. In some embodiments, thefirst stage of patterning comprises etching a first trench portion of atrench within at least a portion of an extreme low-k (ELK) dielectricregion based on a first aspect ratio. In some embodiments, the firststate of patterning comprises forming a first metal line portion of ametal line within the first trench portion of the trench. In someembodiments, the second stage of patterning comprises forming a secondELK dielectric region above at least some of at least one of the firstmetal line portion of the metal line or the ELK dielectric region. Insome embodiments, the second stage of patterning comprises etching asecond trench portion of the trench within at least a portion of thesecond ELK dielectric region based on a second aspect ratio. In someembodiments, the second stage of patterning comprises forming a secondmetal line portion of the metal line within the second trench portion ofthe trench.

According to some aspects, a semiconductor structure for mitigatingpattern collapse is provided, comprising a first etch stop layer (ESL).In some embodiments, the semiconductor structure comprises an extremelow-k (ELK) dielectric region above the first ESL. In some embodiments,the ELK dielectric region comprises at least some of one of a metal lineor an additional metal line associated with a via. For example, theadditional metal line comprises a via portion associated with a firstlateral location, a first metal line portion associated with the firstlateral location, and a second metal line portion associated with asecond lateral location. In some embodiments, the second laterallocation is different from the first lateral location. For example, themetal line comprises a first metal line portion associated with a firstlateral metal line location and a second metal line portion associatedwith a second lateral metal line location. In some embodiments, thesecond lateral metal line location is different from the first lateralmetal line location.

According to some aspects, a method for forming a semiconductorstructure associated with mitigating pattern collapse is provided,comprising etching a first trench portion of a trench within at least aportion of a first extreme low-k (ELK) dielectric region based on afirst aspect ratio. In some embodiments, the method comprises forming afirst metal line portion of a metal line within the first trench portionof the trench. In some embodiments, the method comprises forming asecond ELK dielectric region above at least some of at least one of thefirst metal line portion of the metal line or the first ELK dielectricregion. In some embodiments, the method comprises etching a secondtrench portion of the trench within at least a portion of the second ELKdielectric region based on a second aspect ratio. In some embodiments,the method comprises forming a second metal line portion of the metalline within the second trench portion of the trench.

According to some aspects, a semiconductor structure for mitigatingpattern collapse is provided, comprising a first etch stop layer (ESL).In some embodiments, the semiconductor structure comprises a firstextreme low-k (ELK) dielectric region above the first ESL. For example,the first ELK dielectric region comprises at least some of at least oneof a via portion associated with a first lateral location or a firstmetal line portion associated with a first lateral metal line location.In some embodiments, the semiconductor structure comprises a second ELKdielectric region above the first ELK dielectric region. For example,the second ELK dielectric region comprises a second metal line portionassociated with at least one of a second lateral location or a secondlateral metal line location. In some embodiments, the second lateralmetal line location is different from the first lateral metal linelocation. In some embodiments, the semiconductor structure comprises afirst barrier layer between at least some of the via portion and thesecond metal line portion. In some embodiments, the semiconductorstructure comprises a first barrier layer between at least some of thefirst metal line portion and the second metal line portion.

Although the subject matter has been described in language specific tostructural features or methodological acts, it is to be understood thatthe subject matter of the appended claims is not necessarily limited tothe specific features or acts described above. Rather, the specificfeatures and acts described above are disclosed as example forms ofimplementing the claims.

Various operations of embodiments are provided herein. The order inwhich some or all of the operations are described should not beconstrued as to imply that these operations are necessarily orderdependent. Alternative ordering will be appreciated based on thisdescription. Further, it will be understood that not all operations arenecessarily present in each embodiment provided herein.

It will be appreciated that layers, features, regions, elements, such asthe first etch stop layer (ESL), second ESL, extreme low-k (ELK)dielectric region, second ELK dielectric region, third ELK dielectricregion, first cap region, second cap region, first hard mask (HM)region, second HM region, vias, via portions, via barriers, via barrierportions, metal lines, metal line portions, metal line barriers, metalline barrier portions, trenches, trench portions, etc. depicted hereinare illustrated with particular dimensions relative to one another, suchas structural dimensions or orientations, for example, for purposes ofsimplicity and ease of understanding and that actual dimensions of thesame differ substantially from that illustrated herein, in someembodiments. Additionally, a variety of techniques exist for forming thelayers, features, regions, elements, etc. mentioned herein, such asimplanting techniques, etching techniques, doping techniques, spin-ontechniques, such as spin coating, sputtering techniques such asmagnetron or ion beam sputtering, growth techniques, such as thermalgrowth or deposition techniques such as chemical vapor deposition (CVD),plasma enhanced chemical vapor deposition (PECVD), or atomic layerdeposition (ALD), for example.

Moreover, “exemplary” is used herein to mean serving as an example,instance, illustration, etc., and not necessarily as advantageous. Asused in this application, “or” is intended to mean an inclusive “or”rather than an exclusive “or”. In addition, “a” and “an” as used in thisapplication are generally construed to mean “one or more” unlessspecified otherwise or clear from context to be directed to a singularform. Also, at least one of A and B and/or the like generally means A orB or both A and B. Furthermore, to the extent that “includes”, “having”,“has”, “with”, or variants thereof are used in either the detaileddescription or the claims, such terms are intended to be inclusive in amanner similar to the term “comprising”.

Also, although the disclosure has been shown and described with respectto one or more implementations, equivalent alterations and modificationswill occur based on a reading and understanding of this specificationand the annexed drawings. The disclosure includes all such modificationsand alterations and is limited only by the scope of the followingclaims.

What is claimed is:
 1. A method for forming a semiconductor structureassociated with mitigating pattern collapse, comprising: etching a firsttrench within a first extreme low-k (ELK) dielectric region based on afirst aspect ratio; forming a first metal line within the first trench;forming a second ELK dielectric region above at least one of the firstmetal line or the first ELK dielectric region; etching a second trenchwithin the second ELK dielectric region based on a second aspect ratio;and forming a second metal line within the second trench.
 2. The methodof claim 1, comprising, before the etching a first trench: forming thefirst ELK dielectric region above a first etch stop layer (ESL); forminga cap region above the first ELK dielectric region; and forming a hardmask (HM) region above the first cap region.
 3. The method of claim 2,comprising, after the forming a first metal line and before the forminga second ELK dielectric region: removing at least some of the first capregion; removing at least some of the first HM region; and performing afirst chemical mechanical planarization (CMP) on at least one of thefirst ELK dielectric region or the first metal line.
 4. The method ofclaim 1, comprising performing a first wet clean after the etching afirst trench and before the forming a first metal line.
 5. The method ofclaim 1, comprising, before the etching a second trench: forming a capregion above the second ELK dielectric region; and forming a hard mask(HM) region above the second cap region.
 6. The method of claim 5,comprising, after the forming a second metal line: removing at leastsome of the cap region; removing at least some of the HM region; andperforming a second chemical mechanical planarization (CMP) on at leastone of the second ELK dielectric region or the second metal line.
 7. Themethod of claim 1, comprising, before the forming a first metal line,forming a first metal line barrier at a first lateral metal line barrierlocation within the first ELK dielectric region.
 8. The method of claim1, comprising, before the forming a second metal line, forming a secondmetal line barrier at second lateral metal line barrier location withinthe second ELK dielectric region.
 9. The method of claim 8, comprisingannealing the second metal line barrier.
 10. The method of claim 9,wherein the annealing causes the second metal line barrier to diffuse.11. The method of claim 8, comprising removing a portion of the secondmetal line barrier over the first metal line to expose the first metalline.
 12. The method of claim 1, wherein the etching a second trenchcomprises: etching the second trench to expose a portion of the firstmetal line and a portion of the ELK dielectric region.
 13. The method ofclaim 1, comprising: forming a third ELK dielectric region above atleast one of the second metal line or the second ELK dielectric region;forming a cap region above the third ELK dielectric region; forming ahard mask (HM) region above the cap region; etching a third trenchwithin the third ELK dielectric region based on a third aspect ratio;and forming a third metal line within the third trench.
 14. The methodof claim 1, wherein the second aspect ratio is different than the firstaspect ratio.
 15. A method for forming a semiconductor structureassociated with mitigating pattern collapse, comprising: etching a firsttrench within a first extreme low-k (ELK) dielectric region; forming afirst metal line within the first trench; forming a second ELKdielectric region above at least one of the first metal line or thefirst ELK dielectric region; etching a second trench within the secondELK dielectric region, wherein the second trench is laterally offsetfrom the first trench; and forming a second metal line within the secondtrench.
 16. The method of claim 15, wherein the etching a second trenchcomprises: etching the second trench to expose a portion of the firstmetal line and a portion of the ELK dielectric region.
 17. The method ofclaim 15, comprising, before the forming a second metal line, forming asecond metal line barrier within the second trench.
 18. The method ofclaim 17, wherein the forming a second metal line barrier comprises:forming the second metal line barrier to overlie the first metal lineand the ELK dielectric region.
 19. The method of claim 15, comprising,before the forming a second metal line: forming a first metal linebarrier within the first trench to contact the first ELK dielectricregion; and forming a barrier layer within the second trench to contactthe first metal line barrier and the first metal line.
 20. A method forforming a semiconductor structure associated with mitigating patterncollapse, comprising: etching a first trench within a first extremelow-k (ELK) dielectric region; forming a first metal line barrier withinthe first trench to contact the first ELK dielectric region; forming afirst metal line within the first trench over the first metal linebarrier; forming a second ELK dielectric region above the first metalline; etching a second trench within the second ELK dielectric region;and forming a barrier layer within the second trench to contact thefirst metal line barrier and the first metal line.